1. Technical Field
The present invention relates to a circuit device, an electronic device, and the like.
2. Related Art
With a bridge circuit that drives an external circuit by turning transistors on and off, the timing of switching between on and off varies slightly from transistor to transistor when the transistors are switched between on and off during a transition period between a charge period and a decay period. If a period during which a high-side transistor and a low-side transistor are simultaneously turned on occurs due to the variation in timing, through current flows via the transistors that have been turned on simultaneously.
In order to avoid such through current, JP-A-2008-289143 discloses a method in which a dead time is provided during which all transistors in a bridge circuit are turned off. The document also discloses a method for reducing switching noise during the dead time by monitoring the driving signals of the transistors and controlling, based on the result of monitoring, the bridge circuit so as to maintain either one of two low-side transistors in an on state.
The above-described bridge circuit is facing the need to achieve optimal dead time. In the case where the bridge circuit is used in, for example, a motor driver apparatus, the optimal dead time varies according to the characteristics of the motor to be driven, and thus with the dead time being fixed, it may not be able to avoid through current depending on the type of motor. Also, the required dead time differs due to variations of motor driver apparatuses during the manufacturing process, and it is therefore desirable to optimize the dead time accordingly.